PCI: dwc: Add legacy interrupt callback handler

Currently DesignWare IP does not handle legacy interrupts.
Add a legacy interrupt callback handler.

Signed-off-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
[lorenzo.pieralisi@arm.com: updated commit log]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Kishon Vijay Abraham I <kishon@ti.com>

3 files changed, 17 insertions, 2 deletions

diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c
index dd9c36678cba..1e7b02221eac 100644
--- a/drivers/pci/controller/dwc/pcie-designware-ep.c
+++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
@@ -370,6 +370,16 @@ static const struct pci_epc_ops epc_ops = {
         .stop                   = dw_pcie_ep_stop,
 };
 
+int dw_pcie_ep_raise_legacy_irq(struct dw_pcie_ep *ep, u8 func_no)
+{
+        struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
+        struct device *dev = pci->dev;
+
+        dev_err(dev, "EP cannot trigger legacy IRQs\n");
+
+        return -EINVAL;
+}
+
 int dw_pcie_ep_raise_msi_irq(struct dw_pcie_ep *ep, u8 func_no,
                              u8 interrupt_num)
 {
diff --git a/drivers/pci/controller/dwc/pcie-designware-plat.c b/drivers/pci/controller/dwc/pcie-designware-plat.c
index 35d2291c6ba5..3f8a3aa3a91e 100644
--- a/drivers/pci/controller/dwc/pcie-designware-plat.c
+++ b/drivers/pci/controller/dwc/pcie-designware-plat.c
@@ -87,8 +87,7 @@ static int dw_plat_pcie_ep_raise_irq(struct dw_pcie_ep *ep, u8 func_no,
 
         switch (type) {
         case PCI_EPC_IRQ_LEGACY:
-                dev_err(pci->dev, "EP cannot trigger legacy IRQs\n");
-                return -EINVAL;
+                return dw_pcie_ep_raise_legacy_irq(ep, func_no);
         case PCI_EPC_IRQ_MSI:
                 return dw_pcie_ep_raise_msi_irq(ep, func_no, interrupt_num);
         case PCI_EPC_IRQ_MSIX:
diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h
index e8b97f5a64be..96126fd8403c 100644
--- a/drivers/pci/controller/dwc/pcie-designware.h
+++ b/drivers/pci/controller/dwc/pcie-designware.h
@@ -348,6 +348,7 @@ static inline int dw_pcie_allocate_domains(struct pcie_port *pp)
 void dw_pcie_ep_linkup(struct dw_pcie_ep *ep);
 int dw_pcie_ep_init(struct dw_pcie_ep *ep);
 void dw_pcie_ep_exit(struct dw_pcie_ep *ep);
+int dw_pcie_ep_raise_legacy_irq(struct dw_pcie_ep *ep, u8 func_no);
 int dw_pcie_ep_raise_msi_irq(struct dw_pcie_ep *ep, u8 func_no,
                              u8 interrupt_num);
 int dw_pcie_ep_raise_msix_irq(struct dw_pcie_ep *ep, u8 func_no,
@@ -367,6 +368,11 @@ static inline void dw_pcie_ep_exit(struct dw_pcie_ep *ep)
 {
 }
 
+static inline int dw_pcie_ep_raise_legacy_irq(struct dw_pcie_ep *ep, u8 func_no)
+{
+        return 0;
+}
+
 static inline int dw_pcie_ep_raise_msi_irq(struct dw_pcie_ep *ep, u8 func_no,
                                            u8 interrupt_num)
 {